Fuel distribution manifold system for gas turbine engines

Abstract

A fuel distribution manifold system for a gas turbine engine is disclosed that includes a plurality of interconnected manifold segments, each manifold segment extending between a pair of fittings, each manifold segment including at least one fuel transfer tube and a sealing tube that surrounds the at least one fuel transfer tube, wherein opposed end portions of the at least one fuel transfer tube are dynamically connected to the fittings and opposed end portions of the sealing tube are statically connected to the fittings.

1. A fuel distribution manifold system for a gas turbine engine comprising:
 a plurality of interconnected manifold segments, each manifold segment extending between a pair of fuel injector inlet fittings, each inlet fitting defining a fuel passage for directing fuel to an associated fuel injector, each manifold segment including at least one fuel transfer tube for transferring fuel between the fuel passages of two adjacent inlet fittings and a sealing tube that surrounds the at least one fuel transfer tube to provide leak protection therefor, wherein opposed end portions of the at least one fuel transfer tube are dynamically connected to the inlet fittings and opposed end portions of the sealing tube are statically connected to the inlet fittings, and wherein the sealing tubes of the plurality of interconnected manifold segments are sealingly isolated from the fuel passages of the inlet fittings. 
 
     
     
       2. A fuel distribution manifold system as recited in  claim 1 , wherein the sealing tube includes a resilient section for accommodating axial expansion and contraction of the sealing tube. 
     
     
       3. A fuel distribution manifold system as recited in  claim 2 , wherein the resilient section of the sealing tube is defined by a bellows structure. 
     
     
       4. A fuel distribution manifold system as recited in  claim 3 , wherein the sealing tube is dimensioned and configured such that the bellows structure has a compressive preload. 
     
     
       5. A fuel distribution manifold system as recited in  claim 1 , further comprising a protective cover tube surrounding the sealing tube, wherein one end of the protective cover tube is statically connected to the sealing tube. 
     
     
       6. A fuel distribution manifold system as recited in  claim 1 , wherein each inlet fitting has a main body portion defining a central bore to facilitate fluid communication between adjacent manifold segments. 
     
     
       7. A fuel distribution manifold system as recited in  claim 6 , wherein each inlet fitting has an outlet passage communicating with the central bore for delivering fuel to a fuel injector associated therewith. 
     
     
       8. A fuel distribution manifold system as recited in  claim 1 , wherein the opposed end portions of the at least one fuel transfer tube are dynamically connected to the inlet fittings by annular sealing means. 
     
     
       9. A fuel distribution manifold system as recited in  claim 8 , wherein the annular sealing means are seated at the opposed end portions of the at least one fuel transfer tube. 
     
     
       10. A fuel distribution manifold system as recited in  claim 1 , wherein the opposed ends of the sealing tube are statically connected to the inlet fittings by coupling means. 
     
     
       11. A fuel distribution manifold system as recited in  claim 1 , further comprising means for detecting fuel leakage in the manifold system. 
     
     
       12. A fuel distribution manifold system as recited in  claim 11 , wherein the means for detecting fuel leakage in the manifold system includes drainage passages formed in each inlet fitting to define a continuous drainage path between the plurality of manifold segments. 
     
     
       13. A fuel distribution manifold system as recited in  claim 12 , wherein a leak detection sensor is operatively associated with the drainage path. 
     
     
       14. A fuel distribution manifold system for a gas turbine engine employing staged combustion comprising:
 a) a plurality of circumferentially spaced apart fuel injector inlet fittings extending around a periphery of the engine, the plurality of inlet fittings including adjacent pairs of first and second inlet fittings; and 
 b) a manifold segment extending between adjacent pairs of first and second inlet fittings, each manifold segment including at least first, second and third coaxially arranged fuel transfer tubes, wherein the first fuel transfer tube in each manifold segment is situated to deliver fuel to a first fuel circuit formed in both the first and second inlet fittings, the second fuel transfer tube in each manifold segment is situated to deliver fuel to a second fuel circuit formed in the first inlet fitting and the third fuel transfer tube in each manifold segment is situated to deliver fuel to a third fuel circuit formed in the second inlet fitting. 
 
     
     
       15. A fuel distribution manifold system as recited in  claim 14 , wherein opposed end portions of the coaxially arranged first, second and third fuel transfer tubes of each manifold segment are dynamically connected to the inlet fittings. 
     
     
       16. A fuel distribution manifold system as recited in  claim 15 , wherein the opposed end portions of the coaxially arranged fuel transfer tubes are dynamically connected to the inlet fittings by annular sealing means. 
     
     
       17. A fuel distribution manifold system as recited in  claim 16 , wherein the annular sealing means are seated at the opposed end portions of the coaxially arranged fuel transfer tubes. 
     
     
       18. A fuel distribution manifold system as recited in  claim 15 , wherein each manifold segment includes a sealing tube surrounding the coaxially arranged fuel transfer tubes. 
     
     
       19. A fuel distribution manifold system as recited in  claim 18 , wherein opposed end portions of the sealing tube are statically connected to the inlet fittings. 
     
     
       20. A fuel distribution manifold system as recited in  claim 19 , wherein the sealing tube includes a bellows section for accommodating axial expansion and contraction of the sealing tube. 
     
     
       21. A fuel distribution manifold system as recited in  claim 20 , wherein the sealing tube is dimensioned and configured such that the bellows structure has a compressive preload. 
     
     
       22. A fuel distribution manifold system as recited in  claim 18 , further comprising a protective cover tube surrounding the sealing tube, wherein one end of the protective cover tube is statically connected to the sealing tube. 
     
     
       23. A method of delivering fuel to a gas turbine engine employing staged combustion, comprising the steps of:
 a) providing a fuel distribution manifold assembly including:
 i) a plurality of circumferentially spaced apart fuel injector inlet fittings extending around a periphery of the engine, the plurality of inlet fittings including adjacent pairs of first and second inlet fittings; and 
 ii) a manifold segment extending between adjacent pairs of first and second inlet fittings, each manifold segment including at least first, second and third nested fuel transfer tubes, wherein the first fuel transfer tube in each manifold segment is adapted to deliver fuel to a first fuel circuit of the first and second inlet fittings, the second fuel transfer tube in each manifold segment is adapted to deliver fuel to a second fuel circuit of the first inlet fitting and the third fuel transfer tube in each manifold segment is adapted to deliver fuel to a third fuel circuit of the second inlet fitting; and 
 
 b) delivering fuel to at least one of the fuel circuits through at least one of the fuel transfer tubes. 
 
     
     
       24. A method of delivering fuel to a gas turbine engine according to  claim 23 , wherein the step of delivering fuel to at least one of the fuel circuits includes delivering fuel to the first fuel circuit and at least one other fuel circuit. 
     
     
       25. A method of delivering fuel to a gas turbine engine according to  claim 23 , further comprising the step of staging fuel delivery to the gas turbine engine by:
 i) delivering fuel through the first and second fuel circuits under a first engine operating condition; and 
 
       ii) delivering fuel through the first and third fuel circuits under a second engine operating condition.